Hot blast cupola



Jan. 4, 1938.

C. D. BARR ET AL HOT BLAST CUPOLA Filed Aug. 17, 1935 3 Sheets-Sheet 2Jan. 4, 1938. c. BARR ET AL 2,104,393

HOT BLAST OU'POLA Filed Aug. 17, 1935 3 Sheets-Sheet 3 INVENTORS'.CZHRENCEHEHRF? liq/v L zwsw H01. MES

Patented Jan. 4, 1938 UNITED STATES HOT BLAST CUPOLA Clarence D. Barrand Dan Owen Holmes, Bir mingham, Ala., assignors to American Cast IronPipe Company, Birmingham, Ala., a, corporation of Georgia ApplicationAugust 1'7,

10 Claims.

The present invention relates toimprovements in hot blast cupolas andresides principally in the provision of means for circulating, heatingand delivering air under pressure to the tuyeres which blast the airinto the cupola to effect melting of the products therein used in theproduction of cast metal objects.

One of the principal objects of the present invention is to provide arelatively long path of circulation of the air subject to the heatcreated in the cupola during melting of the metals whereby the air isthoroughly heated before it is delivered to the tuyeres.

Another object of the invention resides in a i i special construction ofconduits through which the air is circulated and providing for easy replacement of the conduits when necessary.

A further object of the invention resides in the provision of means forreadily determining during operation of the cupola, that is, during amelting operation, whether the respective conduits are intact or whetherleaks have occurred therein, and providing for cutting out or makinginoperative such of the conduits as may be leaky so that should one ormore of the conduits become burned out or develop leaks the air will notbe permitted to escape therefrom into the cupola to create a meltingzone above the desired melting zone created by the tuyeres.

The foregoing and other objects and advantages of the invention willbecome more apparent and will be pointed out during the course of thefollowing detail description of the drawings, in which Fig. 1 is avertical central sectional view through a cupola embodying the presentinvention and taken on the line l-! of Fig. 2;

Fig. 2 is a view taken on the line 2-2 of Fig. 1;

Fig. 3 is an enlarged fragmentary view of the upper portions of twopairs of conduits and their couplings, one pair being shown in section;

Fig. 4 is an enlarged fragmentary view partly in section through aportion of the upper end of the cupola and showing the manner of hingingthe conduits;

Fig. 5 is an enlarged detail view partly in section and partlyin'elevation showing the lower ends of the conduits, the inlet andoutlet pipes 5:) with which they communicate and valves for controllingthe fiow of air through said conduits; and

Fig. 6 is a front view of one of the covers for the bustle pipes takenon the line 6-6 of Fig. 5.

In Fig. 1 of the drawings the numeral l indicates the lining of the baseof the cupola composed of refractory material enclosed within a metalshell 2 resting upon a mantle plate 3.

The usual tuyeres 4 communicate with open- 60 ings 5 through the liningl to deliver the blasts 1935, Serial No. 36,744

of air into the cupola to effect the melting of the metal therein. Eachof the tuyeres communicates with a down pipe 6,- the upper ends of whichpipes are connected to and communicate with the lower bustle pipes 'l.

The inner or refractory wall 8 of the cupola, above the base, is formedto accommodate conduits or pipes 9 and I0 arranged in pairs with thelonger pipes 9 of each pair communicating at their lower ends with thelower bustle pipes I; and with the shorter pipes l0 communicating withthe upper bustle pipes II to which the air under pressure is suppliedfrom any suitable source, not shown. It will be noted that the lowerends of the pipes 9 and ID extend through openings in the refractorylining 8 and. the outer shell 12 of the cupola, and as shown best inFig. 5, confront respectively valve heads [3 and I4 lo catedrespectively in the lower and upper bustle pipes l and II. Around thelower ends of each of the pipes 9 and it! within the said bustle pipesis a suitable gasket l5 capable oi withstanding the temperatures towhich they are subjected, due to the passage of the air therethrough andthe heat of the cupola, and adapted to be compressed by gland rings l6drawn up against the gaskets by means of bolts IT and nuts 18 to eiiecta fluid tight joint on each conduit, while permitting movement of theconduits under forces created by expansion and contraction.

The valve heads I3 and M are carried on stems [9 each provided at itsouter end with a handle 20. The stems extend through gland nuts 2|threaded onto the outer ends of bosses 22 through which and packings 23the stems also extend. The bosses 22 which receive the stems it areprovided on plates 24 covering the respective bustle pipes. The saidcover plates 24 are removably attached to the bustle pipes by eye bolts25, the

outer ends of which receive wing nuts 26. Dowel pins 26 are provided tocenter the cover plates. Packing rings 2! are inserted between theplates 24 and the bustle pipes to provide fluid tight joints.

The direction of flow of the air through the bustle pipes, conduits 9and Ill and the tuyres is indicated by the arrows in the drawings, itbeing noted that the air enters the shorter pipes in from the bustlepipes I l and then passes upwardly withr in the cupola wherein the pipesare directly exposed to the temperatures existing in the cupola, andthen down through pipes 9, bustle pipes 1, down pipes 6, and through thetuyeres 4 into the cupola through the openings 5 to create the meltingzone at the bottom of the cupola.

Referring to Figs. 1 and 2 it will be noted that the respective conduits9 and H) are alternately arranged around the interior of the cupola,and, of course, the number of conduits used depends upon the capacity ofthe cupola, and the size of the conduits used.

Each pair of conduits 9 and I0 is connected to its top by couplings 28,shown in detail in Figs. 3 and i, each coupling comprising a hood-likemember having a pair of sockets 29 and 3|] therein which receive theupper ends of the pipes 9 and I6. Packing rings 3i, somewhat similar topiston rings, are seated in grooves in the upper ends of the conduitsand contact the inner walls of the sockets 2i and 30, providing fluidtight joints, and yet permitting relative longitudinal move mentsbetween the conduits and sockets to take care of expansion andcontraction which occurs at various times in the melting process andthereafter. Each of the couplings 28 is provided with upstanding ears 32having alined openings to receive pins 33 maintained againstlongitudinal movement by means of cotter pins 34, or the like. Dependingbrackets 35 are attached to the annular plate 36 at the top of thecupola as by means of rivets or bolts 37, the said brackets being formedto provide cradles 38 to receive pins 33 to hingedly connect each pairof pipes l and I9, and their respective couplings 38, to the top of thecupola.

As is well known hot blast cupolas are charged by dumping the iron,coke, etc., thereinto from the top. In the present case, since theconduits El and i0 and couplings 28 especially at their tops are exposedto contact by the iron and coke being dumped into the cupola, we provideguard plates all each having at its top a hooked end or'flange M toengage over the plate 36' whereby the plates 40 are removably supportedto protect the upper ends of the conduits and their couplings duringcharging of the cupola.

From the foregoing it should be obvious that the air under pressurewhich is supplied to the bustle pipes it, is forced upwardly throughconduits or pipes til, couplings 28, and downwardly through conduits orpipes 9, into the lower bustles I and down pipes 6 to the tuyeres. Thetravel of the air is over a relatively long course with the conduits indirect exposure to the heat within the cupola, so that the air which isdelivered to the tuyres and blasted into the cupola is of a relativelyhigh temperature.

Of course the air entering the bustle H is inducted into the lower endsof the pipes I0, while the air delivered from the pipes 9 into thebustle is emitted under pressure toward the valve heads I3. The operatormay test from time to time whether or not the pipes 9 and I!) and theircouplings are intact or whether they have developed leaks by moving thevalve heads [3 toward the confronting ends of the pipes 9. If the valveheads move against their respective pipes with ease, then the operatorwill know or be warned that there is a leak in one of the pipes 9 or illof the pair being tested. In such event he simply closes the valves l3and I4 against their respective pipes so that the pipes thus closed arecut out and air will be delivered to the tuyeres only through the intactpipes thus assuring maintenance of the melting zone at the bottom of thecupola.

' When it is necessary to replace any of the pipes after a meltingoperation and when the cupola has cooled sufliciently to permit aworkman to enter it, he removes the guard plates 40 which cover thepipes to be repaired, as well as the refractory cement or filler C fromthe lower ends of said pipes, swings the sa d set of pipes on the pivot33 to the dot and dash line position of Fig. 1, after removing the glandrings 16. The conduits or pipes may be then readily withdrawn from thecouplings and new ones inserted therein, after which the conduits arerestored to the full line position of Fig. l. placed around the lowerends of the conduits, the

The packings l5 may then be rior of the bustles for removing andreplacing the gland rings E6, is had simply by removing the proper plate25 which carries the valve with it as a unit.

We have shown and described the pipes or conduits 8 and I9 arranged orcoupled in pairs with the inlet for the air through the lower bustlepipe so that the air is fed upwardly through the pipes it and thendownwardly through the pipes 9. We have also shown and described slipjoints for the ends of said pipes to facilitate removal and replacementthereof.

What we claim is:

1. In a hot blast cupola having a chamber to receive a charge ofmaterials to be melted therein and tuyeres communicating with saidchamber adjacent its lower end to deliver blasts of air thereto tocreate a melting zone at the bottom of the chamber, means to preheat theair delivered by said tuyeres to said chamber comprising bustle pipesinto which the air is delivered under pressure, conduits leading fromsaid bustle pipes upwardly within the cupola, a second set of conduitsleading downwardly in said cupola, couplings connecting the upper endsof adjacent conduits and hingedly supporting the same at their topswithin said cupola, and bustle pipes communicating with said secondconduits and said tuyeres.

2. In a hot blast cupola having a chamber to receive a charge ofmaterials to be melted therein and tuyeres communicating with saidchamber adjacent its lower end to deliver blasts of air thereto tocreate a melting zone at the bottom of the chamber, means to preheat theair delivered by said tuyeres comprising conduits on the interior of thecupola and arranged in pairs with couplings at their upper ends, bustlepipes into which the air under pressure is delivered for heating, bustlepipes into which the heated air is delivered, one of the conduits ofeach pair communicating with said first bustle pipes, and the other ofthe conduits of each pair communicating with the second bustle pipes,and said tuyeres communicating with the second bustle pipes to receivethe heated air therefrom and deliver it into said chamber.

3. In a hot blast cupola having a chamber to receive a charge ofmaterials to be melted therein and tuyres communicating with saidchamber adjacent its lower end to deliver blasts of air thereto tocreate a melting zone at the bottom of the chamber, means to preheat theair delivered by said tuyeres comprising conduits on the interior of thecupola and arranged in pairs with couplings at their upper ends, bustlepipes into which the air under pressure is delivered for heating, bustlepipes into which the heated air is delivered, one of the conduits ofeach pair communicating with said first bustle pipes, and the other ofthe conduits of each pair communicating with the second bustle pipes,said tuyeres communicating with the second bustle pipes to receive theheated air therefrom and deliver it into said chamber, and a hingedconnection for each pair of conduits permitting them to be swunginwardly in the cupola for the purposes specified.

4. In a hot blast cupola having a chamber to receive a charge ofmaterials to be melted therein and tuyeres communicating with saidchamber adjacent its lower end to deliver blasts of air thereto tocreate a melting zone at the bottom of the chamber, means to preheat theair delivered by said tuyeres comprising bustle pipes into which the airis delivered under pressure, conduits leading from said bustle pipesupwardly within the cupola, a second set of conduits leading downwardlyin said cupola, couplings connecting the upper ends of adjacent conduitsand hingedly supporting the same at their tops within said cupola, fluidtight expansion joints between said couplings and conduits, and bustlepipes communicating with said second conduits and said tuyres.

5. The structure of claim 4 wherein the bustle pipes are arrangedexternally around the cupola, with the lower ends of all conduitsextending through the cupola wall in communication with the bustlepipes, and fluid tight joints are provided between said lower ends ofthe conduits and said bustle pipes.

6. In a hot blast cupola having a chamber to receive a charge ofmaterials to be melted therein and tuyeres communicating with saidchamber adjacent its lower end to deliver blasts of air thereto tocreate a melting zone at the bottom of the chamber, means to preheat theair delivered by said tuyres comprising bustle pipes into which the airis delivered under pressure, conduits leading from said bustle pipesupwardly within the cupola, conduits leading downwardly in said cupola,couplings connecting the upper ends of said conduits in pairs andhingedly supporting the same within said cupola, bustle pipescommunicating with said second conduits and said tuyres, and valveswithin said bustle pipes confronting the open ends of said conduits andoperable to permit circulation of air through said pairs of conduits andto cut off said circulation.

7. In a hot blast cupola having a chamber to receive a charge ofmaterials to be melted therein and tuyeres communicating with saidchamber adjacent its lower end to deliver blasts of air thereto tocreate a melting zone at the bottom of the chamber, means to preheat theair delivered by said tuyeres comprising bustle pipes into which the airis delivered under pressure, conduits leading from said bustle pipesupwardly within the cupola, conduits leading downwardly in said cupola,couplings connecting the upper ends of said conduits in pairs andhingedly supporting the same within said cupola, bustle pipescommunicating with said second conduits and said tuyeres, and manuallycontrolled means to determine the continuity of the passage of the airthrough said conduits and couplings and operable to close said conduitsin the event of leakage to prevent delivery of air thereto.

8. In a hot blast cupola having a chamber to receive a charge ofmaterials to be melted therein and tuyeres communicating with saidchamber adjacent its lower end to deliver blasts of air thereto tocreate a melting'zone at the bottom of the chamber, means to preheat theair delivered by said tuyres comprising bustle pipes into which the airis delivered under pressure, conduits leading from said bustle pipesupwardly within the cupola, conduits leading downwardly in said cupola,couplings connecting the upper ends of said conduits in pairs andhingedly supporting the same within said cupola, bustle pipescommunicating with said second conduits and said tuyeres, removableclosures on said bustle pipes and aifording access to the interiorthereof, removable packings around said conduits within said bustlepipes forming fluid tight joints between said bustle pipes and saidconduits, and valves carried by said removable closures operable toclose said conduits.

9. In a hot blast cupola having a chamber to receive a charge ofmaterials to be melted therein and tuyres communicating with saidchamber adjacent its lower end to deliver blasts of air thereto tocreate a melting zone at the bottom of ing from said bustle pipesupwardly within the cupola, conduits leading downwardly in said cupola,bustle pipes into which the heated air is delivered, couplingsconnecting the upper ends of said conduits in pairs and hingedlysupporting the same within said cupola, the lower ends of said conduitsbeing curved and extending through the wall of the cupola into the saidbustle pipes, removable packings forming a fluid tight joint betweensaid lower ends of the conduits and the bustle pipes, and removableclosures on the bustle pipes afiording access to the interior thereoffor removal and replacement of said packings to permit said pairs ofconduits to be swung on their hinges and to be clamped in place.

10. In a hot blast cupola having a chamber to receive a charge ofmaterials to be melted therein I ered by said tuyres comprising bustlepipes into which the air is delivered under pressure, conduits leadingfrom said bustle pipes upwardly within the cupola, conduits leadingdownwardly in said cupola, bustle pipes into which the heated air isdelivered, couplings connecting the upper ends of said conduits in pairsand hingedly supporting the same within said cupola, the lower ends ofsaid conduits being curved and extending through the wall of the cupolainto the said bustle pipes, removable packings forming a fluid tightjoint between said lower ends of the conduits and the bustle pipes, andremovable closures on the bustle pipes affording access to the interiorthereof for removal and replacement of said paokings to permit saidpairs of conduits to be swung on their hinges and to be clamped inplace, and means between said removable closures and said bustle pipesto form a fluid tight joint when the closures are clamped onto saidbustle pipes.

CLARENCE D. BARR.

DAN OWEN HOLMES.

